Korean Journal of Internal Medicine最新文献

Background/aims: Post-acute sequelae of COVID-19 (PASC) are highly heterogeneous; therefore, the pathophysiological mechanisms for PASC remain unclear. In this study, we aimed to examine the immunologic aspects of various PASC symptoms.

Methods: We prospectively enrolled adults aged ≥ 18 years who were diagnosed with COVID-19 between August 2022 and September 2023. Blood samples were collected from all participants, who were interviewed using a questionnaire for PASC symptoms at least once between 1 and 6 months after the COVID-19 diagnosis. For immunological evaluation, plasma concentrations of SARS-CoV-2 spike subunit 1-specific IgG and 33 cytokines were measured using enzyme-linked immunosorbent assays and multiplex-based immunoassay, respectively.

Results: In total, 156 pairs of blood samples and symptom reports from 79 participants were eligible for analysis. The most frequent symptom was fatigue, followed by post exertional malaise, chronic cough, thirst, and brain fog. Gastrointestinal symptoms, chest pain, post exertional malaise, smell/taste change, fatigue, brain fog, abnormal movement, and palpitation were accompanied by significant increases in IL-10, VEGF, and inflammatory cytokines like MIP-1α, IL-1β, IL-6, IL-8, MIG, granzyme A, and CX3CL1 levels, while chronic cough, dizziness, dyspnea, and hair loss were not accompanied by significant differences in cytokine levels.

Conclusion: Symptoms classified into different categories based on the dysfunctional organs may share a common pathophysiology regarding elevation of certain cytokines. Although PASC symptoms are heterogeneous, our findings suggest that T-cell recruitment, thrombosis, and increased vascular permeability might contribute to various symptom clusters sharing common pathophysiological mechanisms.

Medium cut-off (MCO) membranes have emerged as a promising innovation in hemodialysis (HD), offering enhanced clearance of large middle-molecules of uremic toxins compared to traditional HD membranes, while maintaining minimal loss of albumin. The introduction of MCO membranes represents a significant advancement in dialysis technology, potentially reducing the risk of complications associated with inadequate removal of toxins. Compared to high-flux membranes, MCO membranes demonstrate superior efficacy in eliminating large middle-molecules without excessive loss of beneficial proteins, such as albumin. The clinical benefits of MCO membranes extend beyond toxin clearance. They improve quality of life, reduce erythropoiesis-stimulating agent doses and resistance, lower hospitalization rates, and decrease overall healthcare costs. Currently, there is insufficient evidence regarding the effects of MCO membranes on cardiovascular diseases and mortality. Further studies are required to assess their effects on patient outcomes and long-term survival. Future innovations in membrane technology, coupled with ongoing research and development, have the potential to enhance dialysis efficacy further, reduce complications, and facilitate the development of eco-friendly solutions. Additional studies are required to fully explore the potential of MCO membranes and refine their clinical application.

Background/aims: The early detection of gastric cancer is crucial for improving patient outcomes. However, its pathogenesis is not fully understood. The microbiome and extracellular vesicles (EVs) might play a role in gastric carcinogenesis. We aimed to identify gastric-carcinogenesis-associated microbial signatures and evaluate whether these features vary across disease stages.

Methods: We enrolled 141 participants (132 patients with gastric cancer or dysplasia and 9 healthy controls). Microbial-derived EVs were isolated from gastric juice, saliva, serum, and urine. Next-generation sequencing of EV-derived bacterial DNA was performed.

Results: This sequencing revealed the alpha and beta diversities and microbial composition across different disease stages. The alpha diversity was significantly increased in the gastric juice and serum of disease groups. The beta diversity showed significant differences among patient groups. Distinct microbial signatures were observed across different disease stages in all four sample types. Specific bacterial species--Cutibacterium acnes, Streptococcus oralis, Pseudomonas antarctica, Ralstonia insidiosa, and Pseudomonas yamanorum--exhibited unique abundance patterns associated with disease progression, suggesting their potential as noninvasive biomarkers.

Conclusion: Changes in microbial diversity and distinct microbial signatures were observed during gastric carcinogenesis in both gastric juice and extragastric samples, indicating the potential of microbial-derived EVs from liquid biopsy samples as biomarkers for gastric cancer.

This review examines the current status and recent progress in lung cancer screening programs, focusing on low-dose computed tomography (LDCT) and emerging liquid biopsy technologies. In Korea, the National Lung Cancer Screening Program has shown promising results in reducing lung cancer mortality since its implementation in 2019. This review discusses the LDCT screening in Korea, including reductions in short-term mortality, increased screening uptake, and enhanced smoking cessation rates. Results from major international trials, including the National Lung Screening Trial, Nederlands-Leuvens Longkanker Screenings Onderzoek trial, and Multicenter Italian Lung Detection studies, demonstrating the efficacy of LDCT in reducing lung cancer mortality, are reviewed. The potential of liquid biopsy as a complement to LDCT is explored, with a focus on multi-cancer early detection technologies. Notable advances include the Circulating Cell-free Genome Atlas study and the Galleri® test, which have shown promise in detecting cancer at early stages through blood-based screening. We also highlight the challenges and limitations of current screening methods, including the need to improve strategies for screening non-smokers and the importance of balancing benefits against risks. As lung cancer screening continues to advance, combining LDCT and liquid biopsy is anticipated to provide more comprehensive and effective early detection strategies.

Background/aims: The incidence of cholesterol gallstones has increased in the last few decades. This study aimed to evaluate the prevalence of cholesterol gallstones in Korea over a 14-year period, analyze any changes, and identify the predisposing factors.

Methods: A total of 3,909 patients underwent cholecystectomy for gallstones over the 14-year period and were considered for inclusion in this study. Patients were divided into cholesterol and pigment gallstone groups based on gallstone composition, as determined by Fourier Transform Infrared spectroscopy. Patient characteristics were compared between the two groups.

Results: After the exclusion of 259 patients with mixed type gallstones, 3,650 patients were finally included in this study; 2,038 (55.8%) with cholesterol gallstones and 1,612 (44.2%) with pigment gallstones. The proportion of cholesterol gallstones over the 14-year period was 53.8% of the study population as a whole and 77.5% of individuals aged < 50 years. The multivariate analysis revealed that cholesterol gallstones were associated with an age < 50 years, female sex, central obesity, absence of chronic liver diseases, and diabetes mellitus. High density lipoprotein-cholesterol levels showed a tendency toward an association with cholesterol gallstones.

Conclusion: The prevalence of cholesterol gallstones in Korea plateaued 53.8% during the 14-year period. However, given the increasing incidence of cholesterol gallstones among younger individuals, the relative prevalence of cholesterol gallstones may increase in the future.

Background/aims: The impact of coronavirus disease 2019 (COVID-19) on severe exacerbation and mortality in interstitial lung disease (ILD) is unclear. In this study, we evaluate the risk of severe exacerbation and mortality in individuals with ILD following COVID-19.

Methods: Using the Korean National Health Insurance claim-based database, we compared the incidence and risk of severe exacerbation and mortality in individuals with ILD who survived at least one month after COVID-19 (COVID-19 cohort, n = 359) and 1:3 age, sex, and body mass index-matched individuals with ILD who did not have COVID-19 (controls, n = 1,077) between October 8, 2020, and August 30, 2021.

Results: During a mean follow-up of 7.4 months, the COVID-19 cohort had a higher risk of severe exacerbation compared to controls (aHR 2.26, 95% CI 1.38-3.69). During a mean follow-up of 19.6 months, the COVID-19 cohort had a higher risk of death (aHR 2.79, 95% CI 1.63-4.79) compared to controls. When considering COVID-19 severity, the severe COVID-19 group had a higher risk of severe exacerbation and death compared to controls, while the non-severe COVID-19 group did not show increased risk of severe exacerbation or death. In analyses based on ILD subtype, individuals with idiopathic pulmonary fibrosis in the COVID-19 cohort had the highest risk of severe exacerbation and death.

Conclusion: Previous severe COVID-19 was associated with worse clinical outcomes in individuals with ILD, especially in patients with idiopathic pulmonary fibrosis.

Background/aims: This study investigated whether telomere length (TL) in rheumatoid arthritis (RA) patients is shorter than in controls, whether TL in RA patients with interstitial lung disease (RA-ILD) differs from that in those without ILD (RA-nonILD), and whether TL varies according to RA-ILD patterns.

Methods: TL was measured in peripheral leukocytes using quantitative polymerase chain reaction. Results were compared between controls (n = 14), RA (n = 70), RA-ILD (n = 53), and RA-nonILD (n = 53), and between the subgroups with usual interstitial pneumonia (UIP; n = 32) and nonspecific interstitial pneumonia (NSIP; n = 8), with age- and sex-matching in each comparison. The correlation between TL and honeycombing extent was determined.

Results: RA patients had significantly shorter TL (8.3 ± 2.5 kb) than controls (9.5 ± 0.8 kb; p = 0.002). No significant TL difference was found between RA-ILD and RA-nonILD (8.2 ± 2.8 vs 7.7 ± 2.4 kb, p = 0.271). Among RA-ILD, age (p = 0.011), disease activity (p = 0.018), and UIP (p = 0.038) were significantly associated with shortened TL. TL in UIP was shorter than in NSIP (7.4 ± 1.9 vs. 10.0 ± 3.1 kb, p = 0.026). Honeycombing extent in UIP showed a negative correlation with TL but it was nonsignificant (Rho = -0.131, p = 0.387).

Conclusion: This study confirms that RA is associated with shorter TL than in healthy individuals and suggests variations in TL among RA-ILD subtypes, indicating that telomere involvement in pathogenesis may differ by subtype.

Obesity is a major risk factor for heart failure with preserved ejection fraction (HFpEF) and contributes through multiple pathophysiological pathways, including systemic inflammation, neurohormonal activation, and mechanical inhibition. The treatment of obesity has shown significant potential for improving HFpEF outcomes. Sodium-glucose cotransporter 2 inhibitors have emerged as effective treatments for improving symptoms and quality of life in patients with HFpEF while aiding in weight control. Furthermore, a recent demonstration of the clinical benefits of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in HFpEF showed promising results in reducing weight loss, and improving symptoms and clinical outcomes. In this review article, we discuss the association between HFpEF and obesity, the emerging role of GLP-1 RAs, and future directions for medical therapies targeting obesity-associated HFpEF.